I got no well-structured thoughts on the subject. For now it's just a list of points for future elaboration.

Being rational (having common sense) means being persuadable by evidence. Everyone will agree with with, but most people will firmly hold on to their deeply-held irrational convictions.

Majority of opinions we hold are prejudices, biases, and instilled dogmas, rather than tested assumptions that were proven to be correct. Our identities are largely based on these untested opinions. Parting ways with one's identity is an extremely traumatic experience, hence people often would rather die than admit they were spectacularly wrong, even in the face of incontrovertible evidence. Early-formed, quickly-formed and strongly-embraced identities are the surest way to becoming deeply irrational.

Rationality can be made more wide-spread if it's treated as a form of intellectual hygiene: compensating for own biases and stamping out fallacies in ones thinking is not natural, but also not terribly difficult: it can be learned, and the habit of questioning own assumptions can be maintained through practice, like washing hands and brushing teeth. To that end, rhetoric and logic should be taught, with spotting fallacies being the most important skill practiced in lab exercises. Ability to detect untrustworthy sources of information is not a natural proclivity either because it requires ability to adjust for own biases. But that too is a reasonably easy skill to acquire.

Historically, being rational was not the most advantageous behavior: proving that Earth is not at the center of the Universe could get you killed. Allegiance to the tribe was valued more than being right about facts. Repeating disproved theories as an article of faith is just a statement of allegiance to the tribe, to reassure identity, and to get protection and the status among peers. As tribes become less essential in providing security for individuals, mutants who practice rationality are free to use feedback loops for quickly iterating through trial and error in chasing larger status goals: having much larger scale of impact and acquiring more wealth.

Most opinions stated on TVs are not backed up by anything, and usually are pile of fallacies.

The most exciting word for a rational person is "because". Claim without proof means nothing.

In the long run, incentives inevitably trump culture. Aspirations and convictions melt away as compliance with incentives get justified even if incentives contradict views dictated by the culture. Structuring incentives correctly is more important than efficient day-to-day management of performance problems.

Being right in business was always more profitable, but few businesses until now were structured to separate clear performance data from the noise of subjective opinions about the contributor. Also, even if a business was successful vs the competition due to acting in a rational manner, until recently businesses didn't have the global reach to compel the competition to also adopt measuring performance. Current situation where self-measuring businesses get very decisive competitive advantage is the single largest contributing factor for increased rationality in the society in general.

Problem: when measured criteria are too few and simplistic, incentives get narrowed down to focusing on passing the test at any cost, including taking on insane workloads and cheating. Another problem is negative motivational power of measuring one's performance: people get turned off if they fear they may score poorly, leading to the vicious cycle of "low performance => poor score => even lower performance".

Cooperation is more profitable than confrontation. It's obvious on the surface, but in evolutionary terms, humans had such a small amount of resources throughout the history, that someone's benefit almost certainly was somebody's loss, hence zero-sum mentality took hold and still dominates (sports, wars and border conflicts lasting well into the era of potential abundance). That's why it looks like humans programmed not to truly enjoy their success unless competitor loses. Most successful societies are those where trust covers widest possible number of people. That's not really natural, as evolution taught us to trust members only inside small social network: a family, a tribe, ethnic group, etc. That's why corrupt and brutal but familiar local leaders are routinely elected and stay in power as long as they can maintain the fear of the larger groups of outsiders even if the leader produces dismal outcomes for the group.

Adding value (working) has become more profitable than taking property of others (war) very recently in historical terms. That's another facet of the reasoning why humans are ultimately held down by using zero-sum thinking as a default route.

From evolutionary perspective, status among peers is the only important measure of success because it lead to reproductive advantage. Hence physiologically status is more important than wealth because wealth is only a proxy for status. Since status competition is zero-sum by definition, the question is "how much money does one really need" is moot: winner will be satisfied with one penny as long as everyone else got nothing.

If you agree with what I wrote above, you are in danger of being irrational as I made lots of claims without providing any proof or references. :-)

The arc of history certaily bends towards rationality. Big Data revolution is making sure that few decisions will have to be made based on pure opinions and hunches, a.k.a. prejudices, biases and dogmas, which are also known as bad assumptions.

Isn't that exciting that in the fast-approaching evidence-based future incompetent bosses will be quickly found out despite their self-confidence and charisma, full-of-it pundits will be exposed, hot-air-filled politicos will be voted out, and humble, talented and under-appreciated working bees will be promoted and rewarded accordingly?

The answer is easy, it's yes, which is why "Moneyball" is such a bestseller: a wiz-kid mined data to find a factor in player stats that has strongest yet non-obvious correlation with winning. The justice is served to multiple parties: lone wiz kid with proven track record has become an existential threat to the army of highly-paid scouts producing dubious output, the open-minded GM saves his career in the big way, and talented underdog players took their righteous place under the spotlight. Just world, here it comes, and although the road to a giant digital BS filter is going to be bumpy and winding, to me it's pretty clear we are heading in that general direction, and going there pretty fast.

I am also sure* that this just, rational world will turn out to be extremely unpleasant and disappointing for maybe the majority of people. See, right now, while working as a mid-level office drone or a retail sales clerk, or a barista, we all enjoy plausible deniability of being simply under-appreciated and thus we can maintain our self-esteem knowing than some stuck-up/suck-up got ahead simply because life is not fare and bad things happen to good people - us. Now, what if Big Data revolution shows that not only our mediocre bosses do not deserve telling us what to do, but we too turn out to be just as unremarkable as them? What if it turns out that there are people, who are so much more talented that they can add much more value than just about any one of us? What if majority of population is getting paid right now to simply slow down these remarkable individuals and drown their weak, nerdy but brilliant voices in the noise of millions of opinions? Well, even I turn out to be that brilliant individual, who is going to be shown objectively better at doing my job, and many others will have to rush implementing my genius ideas, I fear most people will be so permanently and irreparably depressed that I won't be able to enjoy my new-found appreciation :-). Worse is, of course, if my track record, studied under the microscope of Big Data, turns out to be just "meh" and I will have to leave behind ranks of creators and idea generator and take the spot in the swelling crowd of implementors and assistants, or worse, to become a stipend receiver paid to stay home and not break anything.

As they say, the factory of the future will have only two employees, a man and a dog: the man will be there to feed the dog, and the dog will be there to keep the man from touching the equipment. The only question is are there enough dogs?

*This post will surely one day be mined and ranked by our robot overlords for how well my prediction worked. If I turn out to be right, I hope they will consider me for the dog feeder position :-).